Re: [PATCH 1/6] hash: Introduce ptr_hash_mix routine

[Eric Dumazet <eric.dumazet@gmail.com>]

On Tue, 2012-08-07 at 13:55 +0400, Pavel Emelyanov wrote:

> OK. I was under impression, that hash_ptr was balanced from the fast/effective
> perspective, but I can't argue with you in that area :) So, please, consider
> the below patch instead of #1 and #2 (the rest ones remain unchanged).
> 
> Thanks,
> Pavel
> 
> 
> From: Pavel Emelyanov <xemul@parallels.com>
> Subject: [PATCH 1/5] net: Dont use ifindices in hash fns
> 
> Eric noticed, that when there will be devices with equal indices, some
> hash functions that use them will become less effective as they could.
> Fix this in advance by mixing the net_device address into the hash value
> instead of the device index.
> 
> This is true for arp and ndisc hash fns. The netlabel, can and llc ones
> are also ifindex-based, but that three are init_net-only, thus will not
> be affected.
> 
> Many thanks to David and Eric for the hash32_ptr implementation!
> 
> Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
> ---
>  include/linux/hash.h |   10 ++++++++++
>  include/net/arp.h    |    3 ++-
>  include/net/ndisc.h  |    3 ++-
>  3 files changed, 14 insertions(+), 2 deletions(-)

Signed-off-by: Eric Dumazet <edumazet@google.com>

You should resend other patches, since they are no more on
http://patchwork.ozlabs.org/project/netdev/list/